Just some notes of various issues that we should improve with respect to MultiParameters

• If you provide setpoints but not setpoint_names the setpoints are not used in plots. But stored in set_array in the dataset. Should perhaps raise
• The documentation claims that setpoints can be a tuple of tuples of various types including numpy arrays. This is currently not true. The code checks that the inner type is among nt, DataArray, collections.Sequence, collections.Iteratorwhich numpy.ndarray is not. If you add it to the check it will fail with a type error (see below). I have not tested if DataArrays work correct. Converting to a tuple solved the immediate problem
• Missing setpoint_units
• The multidimensional setpoints are too complicated to use (1D then 2D the 3D etc)